@charset "utf-8";
/* =====================================================================
   株式会社三協 — Website rebuild
   Concept: 「図面から、確かな鉄へ」 blueprint × brushed-steel
   ===================================================================== */

/* ---------- design tokens ---------- */
:root{
  --ink:#15171c;        /* near-black graphite (text) */
  --ink-2:#2b2f37;
  --steel:#575a5f;      /* brand logo grey */
  --steel-2:#878b92;    /* muted grey text */
  --line:#d7dbe1;       /* hairline */
  --line-2:#e8ebef;
  --mist:#eef0f3;       /* pale panel fill */
  --paper:#fafbfc;      /* base background */
  --white:#ffffff;
  --volt:#1b4fcb;       /* brand-derived blue accent */
  --volt-deep:#11357f;  /* darker for hover */
  --volt-tint:rgba(27,79,203,.08);

  --f-jp:"Zen Kaku Gothic New", system-ui, "Hiragino Kaku Gothic ProN", "Noto Sans JP", sans-serif;
  --f-en:"Saira", system-ui, sans-serif;
  --f-mono:"Space Mono", ui-monospace, "SFMono-Regular", monospace;

  --wrap:1200px;
  --gut:clamp(20px, 5vw, 64px);
  --header-h:76px;
}

/* ---------- reset ---------- */
*,*::before,*::after{ box-sizing:border-box; }
html{ scroll-behavior:smooth; scroll-padding-top:var(--header-h); -webkit-text-size-adjust:100%; }
body{
  margin:0;
  font-family:var(--f-jp);
  color:var(--ink);
  background:var(--paper);
  line-height:1.85;
  font-weight:500;
  letter-spacing:.02em;
  -webkit-font-smoothing:antialiased;
  text-rendering:optimizeLegibility;
}
img{ display:block; max-width:100%; height:auto; }
a{ color:inherit; text-decoration:none; }
ul,ol{ list-style:none; margin:0; padding:0; }
h1,h2,h3,p,figure,blockquote,table{ margin:0; }
table{ border-collapse:collapse; }
body.no-scroll{ overflow:hidden; }

.container{ width:100%; max-width:var(--wrap); margin-inline:auto; padding-inline:var(--gut); }
.pc{ display:inline; }
@media (max-width:768px){ .pc{ display:none; } }

/* ---------- shared: eyebrow (製図風ラベル) ---------- */
.eyebrow{
  font-family:var(--f-mono);
  font-size:12px;
  letter-spacing:.22em;
  text-transform:uppercase;
  color:var(--volt);
  display:flex;
  align-items:center;
  gap:.7em;
  margin-bottom:22px;
}
.eyebrow--light{ color:#bcd0ff; }
.eyebrow__mark{
  width:10px; height:10px; flex:none;
  border:1.5px solid currentColor;
  transform:rotate(45deg);
}
.eyebrow__sep{ opacity:.5; }

/* ---------- shared: section titles ---------- */
.sec-title{
  font-family:var(--f-jp);
  font-weight:900;
  font-size:clamp(28px, 4.4vw, 46px);
  line-height:1.28;
  letter-spacing:.01em;
  color:var(--ink);
}
.sec-title--light{ color:var(--white); }
.sec-head{ max-width:760px; margin-bottom:clamp(40px,5vw,64px); }
.sec-lead{
  margin-top:22px; color:var(--steel);
  font-size:clamp(15px,1.6vw,17px); font-weight:500;
}

/* ---------- shared: figure caption (drafting label) ---------- */
.fig-cap{
  font-family:var(--f-mono);
  font-size:11px; letter-spacing:.16em; text-transform:uppercase;
  color:var(--steel-2);
  margin-top:12px;
}
.fig-cap--light{ color:rgba(255,255,255,.66); }

/* ---------- shared: CAD corner brackets (signature) ---------- */
.cad-bracket{
  position:absolute; width:26px; height:26px; z-index:3; pointer-events:none;
  border-color:var(--volt); border-style:solid; border-width:0;
}
.cad-bracket--tl{ top:18px; left:18px; border-top-width:2px; border-left-width:2px; }
.cad-bracket--br{ right:18px; bottom:18px; border-bottom-width:2px; border-right-width:2px; }
.cad-bracket--ink{ border-color:var(--steel); }

/* ---------- shared: buttons ---------- */
.btn{
  display:inline-flex; align-items:center; justify-content:center; gap:.6em;
  font-family:var(--f-jp); font-weight:700; font-size:15px; letter-spacing:.06em;
  padding:15px 32px; border:1.5px solid transparent;
  transition:transform .2s ease, background .2s ease, color .2s ease, border-color .2s ease;
}
.btn--primary{ background:var(--volt); color:#fff; }
.btn--primary:hover{ background:var(--volt-deep); transform:translateY(-2px); }
.btn--ghost{ border-color:rgba(255,255,255,.65); color:#fff; }
.btn--ghost:hover{ background:#fff; color:var(--ink); transform:translateY(-2px); }

/* =====================================================================
   HEADER
   ===================================================================== */
.site-header{
  position:fixed; inset:0 0 auto 0; z-index:50;
  height:var(--header-h);
  display:flex; align-items:center;
  transition:background .3s ease, box-shadow .3s ease, border-color .3s ease;
  border-bottom:1px solid transparent;
}
.site-header__inner{
  width:100%; max-width:var(--wrap); margin-inline:auto;
  padding-inline:var(--gut);
  display:flex; align-items:center; justify-content:space-between;
}
.brand{ position:relative; display:inline-flex; align-items:center; height:30px; }
.brand__logo{ height:50px; width:auto; display:block; transition:opacity .3s ease; }
.brand__logo--dark{ position:absolute; left:0; top:0; opacity:0; }
/* transparent over hero → white logo; scrolled → dark logo */
.site-header.is-solid .brand__logo--light{ opacity:0; }
.site-header.is-solid .brand__logo--dark{ opacity:1; }
.gnav{ display:flex; align-items:center; gap:34px; }
.gnav a{
  font-size:15px; font-weight:700; letter-spacing:.04em; color:#fff;
  position:relative; transition:color .25s ease;
}
.gnav a:not(.gnav__cta)::after{
  content:""; position:absolute; left:0; bottom:-6px; width:0; height:2px;
  background:var(--volt); transition:width .25s ease;
}
.gnav a:not(.gnav__cta):hover::after{ width:100%; }
.gnav__cta{
  padding:10px 22px; background:var(--volt); color:#fff !important;
  font-weight:700; transition:background .25s ease, transform .25s ease;
}
.gnav__cta:hover{ background:var(--volt-deep); transform:translateY(-1px); }

/* solid state (scrolled) */
.site-header.is-solid{
  background:rgba(255,255,255,.92);
  backdrop-filter:saturate(180%) blur(8px);
  border-bottom-color:var(--line);
  box-shadow:0 1px 0 rgba(0,0,0,.02);
}
.site-header.is-solid .gnav a{ color:var(--ink); }
.site-header.is-solid .gnav__cta{ color:#fff !important; }

/* burger */
.burger{
  display:none; width:44px; height:44px; border:0; background:transparent;
  cursor:pointer; padding:0; position:relative; z-index:60;
}
.burger span{
  position:absolute; left:9px; width:26px; height:2px; background:#fff;
  transition:transform .3s ease, opacity .2s ease, background .3s ease;
}
.burger span:nth-child(1){ top:14px; }
.burger span:nth-child(2){ top:21px; }
.burger span:nth-child(3){ top:28px; }
.site-header.is-solid .burger span{ background:var(--ink); }
.burger.is-open span,
.site-header.is-solid .burger.is-open span{ background:#fff; }
.burger.is-open span:nth-child(1){ transform:translateY(7px) rotate(45deg); }
.burger.is-open span:nth-child(2){ opacity:0; }
.burger.is-open span:nth-child(3){ transform:translateY(-7px) rotate(-45deg); }

/* ---------- drawer ---------- */
.drawer{
  position:fixed; top:0; right:0; z-index:55;
  width:min(82vw, 360px); height:100dvh;
  background:var(--ink); color:#fff;
  padding:calc(var(--header-h) + 24px) 34px 34px;
  transform:translateX(100%); transition:transform .4s cubic-bezier(.22,1,.36,1);
  display:flex; flex-direction:column; justify-content:space-between;
}
.drawer.is-open{ transform:translateX(0); }
.drawer__close{
  position:absolute; top:16px; right:18px;
  width:48px; height:48px; border:0; background:transparent; cursor:pointer;
  color:#fff; font-size:30px; line-height:1; display:grid; place-items:center;
  border:1px solid rgba(255,255,255,.28); border-radius:50%;
  transition:background .2s ease, border-color .2s ease;
}
.drawer__close:hover{ background:rgba(255,255,255,.12); border-color:#fff; }
.drawer__close-label{
  position:absolute; right:74px; top:50%; transform:translateY(-50%);
  font-family:var(--f-mono); font-size:11px; letter-spacing:.18em; color:rgba(255,255,255,.6);
  text-transform:uppercase; pointer-events:none;
}
.drawer__nav{ display:flex; flex-direction:column; }
.drawer__nav a{
  padding:18px 0; border-bottom:1px solid rgba(255,255,255,.12);
  font-size:18px; font-weight:700;
  display:flex; flex-direction:column; gap:2px;
}
.drawer__nav a .en{
  font-family:var(--f-mono); font-size:11px; letter-spacing:.2em;
  text-transform:uppercase; color:var(--volt); font-weight:400;
}
.drawer__foot{ font-size:13px; color:rgba(255,255,255,.6); }
.drawer__tel{
  display:block; font-family:var(--f-en); font-weight:700; font-size:26px;
  letter-spacing:.04em; color:#fff; margin-bottom:6px;
}
.drawer-veil{
  position:fixed; inset:0; z-index:54; background:rgba(10,12,16,.5);
  opacity:0; visibility:hidden; transition:opacity .4s ease, visibility .4s ease;
}
.drawer-veil.is-open{ opacity:1; visibility:visible; }

/* =====================================================================
   HERO
   ===================================================================== */
.hero{
  position:relative; min-height:100svh;
  display:flex; align-items:flex-end;
  padding:calc(var(--header-h) + 40px) 0 0;
  overflow:hidden; color:#fff;
}
.hero__media{ position:absolute; inset:0; z-index:0; }
.hero__media img{ width:100%; height:100%; object-fit:cover; object-position:center; }
.hero__scrim{
  position:absolute; inset:0;
  background:linear-gradient(100deg, rgba(12,14,20,.86) 0%, rgba(12,14,20,.55) 42%, rgba(12,14,20,.15) 78%);
}
.hero__grid{
  position:absolute; inset:0; z-index:1; pointer-events:none; opacity:.5;
  background-image:
    linear-gradient(rgba(255,255,255,.07) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,.07) 1px, transparent 1px);
  background-size:64px 64px;
  -webkit-mask-image:linear-gradient(100deg, #000 0%, transparent 60%);
          mask-image:linear-gradient(100deg, #000 0%, transparent 60%);
}
.hero .cad-bracket{ width:40px; height:40px; }
.hero .cad-bracket--tl{ top:calc(var(--header-h) + 24px); left:24px; border-color:#fff; }
.hero .cad-bracket--br{ right:24px; bottom:88px; border-color:#fff; }

.hero__inner{
  position:relative; z-index:4;
  width:100%; max-width:var(--wrap); margin-inline:auto;
  padding:0 var(--gut) clamp(70px,9vw,120px);
}
.hero__title{
  font-family:var(--f-jp); font-weight:900;
  font-size:clamp(36px, 7vw, 84px);
  line-height:1.16; letter-spacing:.005em;
  text-shadow:0 2px 30px rgba(0,0,0,.3);
  margin-bottom:26px;
}
.hero__lead{
  font-size:clamp(14px,1.7vw,18px); font-weight:500;
  color:rgba(255,255,255,.9); max-width:640px; margin-bottom:34px;
}
.hero__actions{ display:flex; flex-wrap:wrap; gap:14px; margin-bottom:48px; }
.hero__spec{
  display:flex; flex-wrap:wrap; gap:0;
  border-top:1px solid rgba(255,255,255,.22);
}
.hero__spec li{
  font-family:var(--f-mono); font-size:13px; letter-spacing:.04em;
  color:rgba(255,255,255,.92);
  padding:16px 26px 0 0; margin-right:26px;
  display:flex; flex-direction:column; gap:4px;
}
.hero__spec .k{ font-size:10px; letter-spacing:.2em; color:#bcd0ff; }

.dim-line{
  position:absolute; left:0; right:0; bottom:34px; z-index:4;
  height:1px; background:rgba(255,255,255,.28);
  max-width:var(--wrap); margin-inline:auto;
}
.dim-line::before, .dim-line::after{
  content:""; position:absolute; top:-4px; width:1px; height:9px; background:rgba(255,255,255,.5);
}
.dim-line::before{ left:var(--gut); }
.dim-line::after{ right:var(--gut); }
.dim-line__label{
  position:absolute; left:var(--gut); top:-26px;
  font-family:var(--f-mono); font-size:10px; letter-spacing:.2em;
  color:rgba(255,255,255,.6); text-transform:uppercase;
}

/* =====================================================================
   NEWS
   ===================================================================== */
.news{ background:var(--white); border-bottom:1px solid var(--line-2); }
.news__inner{ display:flex; align-items:center; gap:clamp(20px,4vw,56px); padding-block:24px; }
.news__title{
  flex:none; display:flex; align-items:baseline; gap:12px;
  font-weight:900; font-size:17px;
}
.news__title .en{
  font-family:var(--f-en); color:var(--volt); font-size:20px; letter-spacing:.04em;
}
.news__list{ flex:1 1 auto; min-width:0; }
.news__list li{ display:flex; align-items:center; gap:18px; font-size:14.5px; }
.news__list time{ font-family:var(--f-mono); color:var(--steel-2); flex:none; }
.news__tag{
  flex:none; font-size:11px; letter-spacing:.1em; color:var(--volt);
  border:1px solid var(--volt); padding:2px 10px;
}
.news__text{ color:var(--ink-2); overflow:hidden; text-overflow:ellipsis; white-space:nowrap; }

/* =====================================================================
   ABOUT
   ===================================================================== */
.about{ padding-block:clamp(80px,11vw,140px); }
.about__grid{
  display:grid; grid-template-columns:1.05fr .95fr; gap:clamp(40px,6vw,90px);
  align-items:center;
}
.about__text{
  margin-top:10px; color:var(--ink-2); font-size:clamp(15px,1.6vw,17px);
  font-weight:500;
}
.motto{
  position:relative; margin-top:38px; padding-left:26px;
  font-family:var(--f-jp); font-weight:900;
  font-size:clamp(22px,2.8vw,30px); line-height:1.5; color:var(--ink);
}
.motto__mark{ position:absolute; left:0; top:6px; bottom:6px; width:4px; background:var(--volt); }
.about__fig{ position:relative; }
.about__fig img{ width:100%; aspect-ratio:5/4; object-fit:cover; }

/* =====================================================================
   CAPABILITIES (dark)
   ===================================================================== */
.caps{ background:var(--ink); color:#fff; padding-block:clamp(80px,11vw,140px); position:relative; }
.caps__head{ max-width:720px; margin-bottom:clamp(44px,5vw,68px); }
.caps__lead{ margin-top:22px; color:rgba(255,255,255,.72); font-size:clamp(15px,1.6vw,17px); font-weight:500; }
.process{
  display:grid; grid-template-columns:repeat(5,1fr);
  column-gap:clamp(22px,2.6vw,46px); row-gap:44px;
}
.process__step{
  position:relative; padding-top:26px;
  border-top:1px solid rgba(255,255,255,.22);
}
.process__no{
  font-family:var(--f-en); font-weight:800; font-size:36px; letter-spacing:.02em;
  color:var(--volt); display:block; margin-bottom:18px; line-height:1;
}
.process__step h3{ font-size:17px; font-weight:900; margin-bottom:12px; }
.process__step p{ font-size:13.5px; font-weight:400; color:rgba(255,255,255,.66); line-height:1.85; }
.caps__fig{ position:relative; margin-top:clamp(44px,6vw,72px); }
.caps__fig img{ width:100%; aspect-ratio:21/8; object-fit:cover; object-position:center 35%; }

/* =====================================================================
   PRODUCTS
   ===================================================================== */
.products{ padding-block:clamp(80px,11vw,140px); }
.prod-tags{
  display:flex; flex-wrap:wrap; gap:10px; margin-bottom:clamp(36px,4vw,52px);
}
.prod-tags li{
  font-size:13.5px; font-weight:700; letter-spacing:.04em; color:var(--steel);
  border:1px solid var(--line); padding:8px 16px; background:var(--white);
}
.gallery{
  display:grid; grid-template-columns:repeat(4,1fr); gap:18px;
}
.gallery__item figure{ margin:0; }
.gallery__item img{
  width:100%; aspect-ratio:3/4; object-fit:contain;
  background:var(--mist); border:1px solid var(--line-2); padding:14px;
  transition:transform .4s ease;
}
.gallery__item figure:hover img{ transform:scale(1.02); }
.gallery__item figcaption{
  font-family:var(--f-mono); font-size:12px; letter-spacing:.06em; color:var(--steel);
  margin-top:12px; display:flex; align-items:center; gap:10px;
}
.gallery__item .num{ color:var(--volt); font-weight:700; }

/* =====================================================================
   COMPANY
   ===================================================================== */
.company{ padding-block:clamp(80px,11vw,140px); background:var(--mist); }
.company__grid{
  display:grid; grid-template-columns:1fr 1fr; gap:clamp(36px,5vw,72px);
  margin-bottom:clamp(48px,6vw,80px);
}
.greeting__title, .access__title{
  display:flex; align-items:baseline; gap:14px;
  font-weight:900; font-size:22px; margin-bottom:24px;
}
.greeting__title .en, .access__title .en{
  font-family:var(--f-en); color:var(--volt); font-size:22px; letter-spacing:.04em;
}
.greeting__text{ color:var(--ink-2); font-size:15.5px; font-weight:500; }
.greeting__name{ margin-top:24px; font-weight:900; font-size:16px; }
.greeting__name span{ font-weight:500; color:var(--steel-2); margin-left:8px; font-size:14px; }

.profile__table{ width:100%; background:var(--white); border:1px solid var(--line); }
.profile__table th, .profile__table td{
  text-align:left; vertical-align:top; padding:16px 20px;
  border-bottom:1px solid var(--line-2); font-size:14.5px;
}
.profile__table tr:last-child th, .profile__table tr:last-child td{ border-bottom:0; }
.profile__table th{
  width:34%; font-weight:700; color:var(--steel);
  background:var(--paper); white-space:nowrap;
  font-family:var(--f-mono); font-size:13px; letter-spacing:.04em;
}
.profile__table td{ color:var(--ink-2); font-weight:500; }

.access__map{
  border:1px solid var(--line); background:var(--white); padding:8px;
  line-height:0;
}
.access__map iframe{ display:block; width:100%; }

/* =====================================================================
   CONTACT
   ===================================================================== */
.contact{ position:relative; }
.contact__grid{ position:relative; overflow:hidden; color:#fff; }
.contact__bg{ position:absolute; inset:0; width:100%; height:100%; object-fit:cover; z-index:0; }
.contact__scrim{ position:absolute; inset:0; z-index:1; background:linear-gradient(120deg, rgba(17,53,127,.92), rgba(12,14,20,.86)); }
.contact .cad-bracket{ width:34px; height:34px; border-color:#fff; z-index:3; }
.contact .cad-bracket--tl{ top:24px; left:24px; }
.contact .cad-bracket--br{ right:24px; bottom:24px; }
.contact__inner{
  position:relative; z-index:4;
  max-width:var(--wrap); margin-inline:auto; padding:clamp(70px,9vw,120px) var(--gut);
}
.contact__title{
  font-family:var(--f-jp); font-weight:900; font-size:clamp(28px,4.4vw,48px);
  line-height:1.28; margin-bottom:18px;
}
.contact__lead{ color:rgba(255,255,255,.82); font-size:clamp(15px,1.6vw,17px); margin-bottom:42px; }
.contact__methods{ display:flex; flex-wrap:wrap; gap:18px; margin-bottom:30px; }
.contact__card{
  flex:1 1 280px; min-width:0;
  display:flex; flex-direction:column; gap:6px;
  background:rgba(255,255,255,.06); border:1px solid rgba(255,255,255,.28);
  padding:26px 30px; transition:background .25s ease, transform .25s ease, border-color .25s ease;
}
.contact__card:hover{ background:rgba(255,255,255,.12); border-color:#fff; transform:translateY(-3px); }
.contact__k{ font-family:var(--f-mono); font-size:12px; letter-spacing:.2em; color:#bcd0ff; }
.contact__v{ font-family:var(--f-en); font-weight:700; font-size:clamp(26px,3.4vw,38px); letter-spacing:.02em; }
.contact__note{ font-size:13px; color:rgba(255,255,255,.62); }
.contact__addr{ font-size:14px; color:rgba(255,255,255,.7); }

/* =====================================================================
   FOOTER
   ===================================================================== */
.site-footer{ background:var(--ink); color:#fff; padding-top:clamp(50px,6vw,72px); }
.site-footer__inner{
  display:flex; flex-wrap:wrap; justify-content:space-between; gap:32px;
  padding-bottom:clamp(40px,5vw,56px); border-bottom:1px solid rgba(255,255,255,.12);
}
.site-footer__logo{ height:34px; margin-bottom:18px; }
.site-footer__addr{ font-size:13.5px; color:rgba(255,255,255,.6); line-height:1.9; }
.site-footer__nav{ display:flex; flex-wrap:wrap; gap:14px 28px; align-content:flex-start; }
.site-footer__nav a{ font-size:14px; font-weight:700; color:rgba(255,255,255,.86); transition:color .2s ease; }
.site-footer__nav a:hover{ color:var(--volt); }
.site-footer__copy{
  font-family:var(--f-mono); font-size:11px; letter-spacing:.16em; text-transform:uppercase;
  color:rgba(255,255,255,.4); text-align:center; padding:24px 0 28px;
}

/* ---------- page top ---------- */
.pagetop{
  position:fixed; right:22px; bottom:22px; z-index:40;
  width:48px; height:48px; display:grid; place-items:center;
  background:var(--volt); color:#fff; font-size:18px;
  opacity:0; transform:translateY(12px); pointer-events:none;
  transition:opacity .3s ease, transform .3s ease, background .25s ease;
}
.pagetop.is-show{ opacity:1; transform:none; pointer-events:auto; }
.pagetop:hover{ background:var(--volt-deep); }

/* =====================================================================
   reveal animation
   ===================================================================== */
.reveal{ opacity:0; transform:translateY(26px); transition:opacity .7s ease, transform .7s cubic-bezier(.22,1,.36,1); }
.reveal.is-in{ opacity:1; transform:none; }

/* =====================================================================
   RESPONSIVE
   ===================================================================== */
@media (max-width:1024px){
  .gallery{ grid-template-columns:repeat(3,1fr); }
  .process{ grid-template-columns:repeat(3,1fr); }
}

@media (max-width:768px){
  :root{ --header-h:62px; }
  .gnav{ display:none; }
  .burger{ display:block; }

  .hero{ min-height:88svh; align-items:flex-end; }
  .hero__scrim{ background:linear-gradient(180deg, rgba(12,14,20,.5) 0%, rgba(12,14,20,.55) 40%, rgba(12,14,20,.82) 100%); }
  .hero__spec li{ flex:1 1 100%; padding-right:0; margin-right:0; border-bottom:1px solid rgba(255,255,255,.14); padding-block:14px; }
  .hero .cad-bracket{ display:none; }

  .news__inner{ flex-direction:column; align-items:flex-start; gap:12px; }
  .news__list li{ flex-wrap:wrap; gap:10px; }
  .news__text{ white-space:normal; }

  .about__grid{ grid-template-columns:1fr; }
  .about__fig{ order:-1; }

  .process{ grid-template-columns:1fr 1fr; column-gap:24px; row-gap:34px; }
  .caps__fig img{ aspect-ratio:16/10; }

  .gallery{ grid-template-columns:repeat(2,1fr); gap:12px; }
  .company__grid{ grid-template-columns:1fr; }

  .contact__methods{ flex-direction:column; }
}

@media (max-width:420px){
  .gallery{ grid-template-columns:1fr 1fr; }
  .process{ grid-template-columns:1fr; }
}

/* ---------- reduced motion ---------- */
@media (prefers-reduced-motion: reduce){
  html{ scroll-behavior:auto; }
  .reveal{ opacity:1; transform:none; transition:none; }
  *{ animation:none !important; }
}

/* ---------- focus visibility ---------- */
a:focus-visible, button:focus-visible{
  outline:2px solid var(--volt); outline-offset:3px;
}
.site-header.is-solid a:focus-visible{ outline-color:var(--volt); }